WIP on PostgreSQL integration tests

tests/Integration/PostgreSQL/DocumentListTest.php

@@ -22,7 +22,7 @@ describe('::create()', function () {
     });
 });
 
-describe('::items()', function () {
+describe('->items()', function () {
     test('enumerates items in the list', function () {
         $list = DocumentList::create(Query::selectFromTable(ThrowawayDb::TABLE), [],
             new DocumentMapper(TestDocument::class));
@@ -43,3 +43,54 @@ describe('::items()', function () {
             ->and(fn () => iterator_to_array($list->items()))->toThrow(DocumentException::class);
     });
 });
+
+describe('->hasItems()', function () {
+    test('returns false when no items are in the list', function () {
+        expect(DocumentList::create(
+                Query::selectFromTable(ThrowawayDb::TABLE) . " WHERE (data->>'num_value')::numeric < 0", [],
+                new DocumentMapper(TestDocument::class)))
+            ->not->toBeNull()
+            ->hasItems()->toBeFalse();
+    });
+    test('returns true when items are in the list', function () {
+        $list = DocumentList::create(Query::selectFromTable(ThrowawayDb::TABLE), [],
+            new DocumentMapper(TestDocument::class));
+        expect($list)->not->toBeNull()->hasItems()->toBeTrue();
+        foreach ($list->items() as $ignored) {
+            expect($list)->hasItems()->toBeTrue();
+        }
+        expect($list)->hasItems()->toBeFalse();
+    });
+});
+
+describe('->map()', function () {
+    test('transforms the list', function () {
+        $list = DocumentList::create(Query::selectFromTable(ThrowawayDb::TABLE), [],
+            new DocumentMapper(TestDocument::class));
+        expect($list)->not->toBeNull()->hasItems()->toBeTrue();
+        foreach ($list->map(fn($doc) => strrev($doc->id)) as $mapped) {
+            expect(['eno', 'owt', 'eerht', 'ruof', 'evif'])->toContain($mapped);
+        }
+    });
+});
+
+describe('->iter()', function () {
+    test('walks the list', function () {
+        $list = DocumentList::create(Query::selectFromTable(ThrowawayDb::TABLE), [],
+            new DocumentMapper(TestDocument::class));
+        expect($list)->not->toBeNull()->hasItems()->toBeTrue();
+        $splats = [];
+        $list->iter(function ($doc) use (&$splats) { $splats[] = str_repeat('*', strlen($doc->id)); });
+        expect(implode(' ', $splats))->toBe('*** *** ***** **** ****');
+    });
+});
+
+describe('->mapToArray()', function () {
+    test('creates an associative array', function () {
+        $list = DocumentList::create(Query::selectFromTable(ThrowawayDb::TABLE), [],
+            new DocumentMapper(TestDocument::class));
+        expect($list)->not->toBeNull()->hasItems()->toBeTrue()
+            ->and($list->mapToArray(fn($it) => $it->id, fn($it) => $it->value))
+            ->toBe(['one' => 'FIRST!', 'two' => 'another', 'three' => '', 'four' => 'purple', 'five' => 'purple']);
+    });
+});